Inherited chromosomal translocation in two families (t(4q-;13q+) and t(5q-; 13q+))

A Case of Inherited t(4;10)(q26;q26.2) Chromosomal Translocation Elucidated by Multiple Chromosomal and Molecular Analyses. Case Report and Review of the Literature

We present a complex chromosomal anomaly identified using cytogenetic and molecular methods. The child was diagnosed during the neonatal period with a multiple congenital anomalies syndrome characterized by: flattened occipital region; slight turricephaly; tall and broad forehead; hypertelorism; deep-set eyes; down slanting and short palpebral fissures; epicanthic folds; prominent nose with wide root and bulbous tip; microstomia; micro-retrognathia, large, short philtrum with prominent reliefs; low set, prominent ears; and congenital heart disease. The GTG banding karyotype showed a 46,XY,der(10)(10pter→10q26.2::4q26→4qter) chromosomal formula and his mother presented an apparently balanced reciprocal translocation: 46,XX,t(4;10)(q26;q26.2). The chromosomal anomalies of the child were confirmed by MLPA, and supplementary investigation discovered a quadruplication of the 4q35.2 region. The mother has a triplication of the same chromosomal fragment (4q35.2). Using array-CGH, we described the anomalies completely. Thus, the boy has a 71,057 kb triplication of the 4q26-q35.2 region, a 562 kb microdeletion in the 10q26.3 region, and a 795 kb quadruplication of the 4q35.2 region, while the mother presents a 795 kb triplication of the 4q35.2 region. Analyzing these data, we consider that the boy's phenotype is influenced only by the 4q partial trisomy. We compare our case with similar cases, and we review the literature data.

Craniosynostosis associated with distal 5q-trisomy: further evidence that extra copy of MSX2 gene leads to craniosynostosis

Distal 5q-trisomy has been reported in less than 30 patients, with craniosynostosis present in five. We report two new patients with distal 5q-trisomy craniosynostosis. Patient 1 had mild Kleeblattschädel with synostosis of multiple sutures together with wide and medially deviated thumbs and halluces, indicative of Pfeiffer syndrome. Cytogenetic and CGH analyses showed a karyotype of 46,XY,der(10)t(5;10)(q33;q26.3). Patient 2 had a prominent forehead and ridging of the metopic suture. Craniosynostosis of the metopic suture was shown by CT scan. Cytogenetic and CGH analyses disclosed a karyotype of 46,XX,der(17)t(5;17)(q35.1;p13.3). Of the 22 previously reported patients, all had microcephaly and 14 had an abnormal skull shape. Our results support the previous finding that distal 5q-trisomy together with an extra copy of the MSX2 gene leads to abnormal closure of sutures and craniosynostosis.

[De novo partial duplication of the distal segment of the long arm of chromosome 5 (q31--> qter). Report of a new case]

We report a case of de novo partial duplication of the distal segment of the long arm of chromosome 5 (q31--> qter). The patient showed dysmorphic features (flat face, short and horizontal palpebral fissures, depressed and broad nasal bridge, wide nose with hypoplastic alae nasae, short and flat philtrum, high arched palate, micrognathia, anomalies of the ears), redundant adipose panniculus of the neck, proximal shortening of the limbs, flexion contractures, long and distally widened fingers, bilateral clubfoot, single umbilical artery, hypoplasia of lung and pulmonary arteries, atrial septal defect and patent ductus arteriosus. She died 23 hours after birth from respiratory failure. Chromosome analysis with high resolution GTG bands showed 46,XX,1p1, which was interpreted as a partial duplication of the distal long arm of chromosome 5 (q31--> qter). Fluorescence in situ hybridization analyses with whole chromosome painting technique for chromosome 5 proved that this extra region belonged to chromosome 5. Our case is the first to have a de novo partial duplication of this chromosome segment.

Duplication within chromosome 5q characterized by fluorescence in situ hybridization

We present a 16-month-old boy with developmental delay, minor anomalies, small penis, and lymphedema of the upper limbs. Routine cytogenetic analysis suspected a duplication of 5q. Fluorescent in situ hybridization (FISH) with a cosmid probe (MCC at the 5q22 APC region) showed tandemly duplicated fluorescent signals on one of chromosomes 5, whereas FISH with three YAC probes (TYAC12 at 5q35, HTY3182 at 5q34, and TYAC139 at 5q31) did not give duplicated signals. These findings indicate a duplication of 5q22 band in one chromosome 5. The boy we describe here is the first case of a pure partial duplication of 5q to be proven by FISH techniques. A review of previously reported cases of putative partial 5q duplication showed no consistent phenotype.

Unbalanced 5;16 translocation in a boy with papillary thyroid carcinoma

This is the first reported case of an unbalanced chromosome rearrangement resulting in trisomy 5q35.5-->qter and monosomy 16p 13.3-->pter, in a boy with mental and growth retardation, minor anomalies, and a history of bilateral papillary thyroid carcinoma. This was the result of a familial balanced translocation. The clinical and cytogenetic manifestations of the case are presented and the possible role of the chromosomal rearrangement in the etiology of the thyroid carcinoma is discussed.

Calcification of basal ganglia in a patient with partial trisomy 5q and partial monosomy 18q

A patient with partial trisomy for the distal segment of the long arm of chromosome 5 (q35.1-->qter) with partial 18q monosomy is presented. The mother of the patient was phenotypically normal and was proved to be a carrier of a reciprocal translocation of the long arm of chromosomes 5 and 18 46,XX,t(5;18)(q35.1;q23). The patient shows mild mental retardation, short stature, mild obesity, dysmorphic face, eczema, minor malformations of the extremities, and bilateral intracranial calcification in the basal ganglia. Most of the clinical manifestations of the patient are compatible with the previously reported clinical features of partial trisomy of the distal segment of 5q. However, the calcification of bilateral basal ganglia has not been reported for this chromosomal anomaly.

Dosage analysis at the CSF1 and CSF1R loci in a new case of partial trisomy 5q

We report on a new case of trisomy for the distal portion of chromosome 5q, arising from a maternal balanced translocation, t(5;22)(q33;q13). The patient presented with mental retardation and peculiar craniofacial anomalies, similar to those already described in trisomy 5q3. Overall, the phenotype bore some resemblance to that of the Brachmann-De Lange syndrome. The extent of the duplicated region was investigated through a combined molecular-cytogenetic approach, using 5q probes for gene dosage analysis by Southern blot, which allowed confirmation of breakpoint assignment to band 5q33. Since most manifestations of trisomy 5q3 are observed in patients with duplications spanning 5q34-qter, it seems that the critical sequences involved in phenotype determination lie within this very distal segment.

The trisomy (5)(q31-qter) syndrome: study of a family with a t(5:14) translocation

We report a child with multiple malformations caused by trisomy for the distal part of the long arm of chromosome No 5. A neonatal diagnosis of Down's syndrome had previously been made on the basis of clinical examination and the detection of an additional chromosome not unlike No 21. A subsequent clinical re-evaluation, with the cooperation of the parents who permitted further studies, led to the confirmation of the true diagnosis. The mother was the carrier of a balanced translocation between chromosome No 5 and No 14. The child had severe growth and psychomotor retardation and characteristic features: microcephaly, antimongoloid slant, epicanthus, low set ears, down-turned mouth, and long upper lip. She was hypertonic and a congenital heart disease (atrial septal defect) was present. We have compared this case with others known to be trisomic for segment 5q31-qter.

Partial trisomy 5q and partial monosomy 5q within the same family

The observation of partial trisomy for 5q31-5qter and partial monosomy for the same segment in two offspring within the same family is presented. Their normal mother was a balanced carrier of a reciprocal translocation 46,XX,t(5;10) (q31.3;q26). The trisomic female had craniofacial dysplasia, a short neck, clinodactyly of the 5th fingers, a small umbilical hernia, arhinencephalia, cerebellar hypoplasia, atrial septal defect, an accessory spleen, bifid uterus and vagina, hypoplastic ovaries. Potter syndrome with cystic dysplasia of the left kidney and agenesis of the right, urethral atresia, uterus unicornus with utero-urethral fistula, true hermaphroditism with two ovaries and one testicle were found in her stillborn sister. Analysis of the manifestations of monosomy 5q and trisomy 5q in the same family supports a well known fact that the effects of deletions are more pronounced than those of duplications for the same segments.

Partial proximal trisomy of the long arm of chromosome 5 (q13 leads to q22) resulting from maternal insertion der ins (10;5)

Five members of our study family were carriers of a balanced insertion (10;5) (q22;q13;q22). One of the children had psychomotor retardation and malformations resulting from a partial trisomy of the proximal long arm of chromosome 5, having received the maternal der(10). Amniocentesis identified another case of partial proximal trisomy in a fetus of a subsequent pregnancy. This clinical and family study is compared with two other published cases of proximal trisomy 5q.